ADVANCES in NATURAL and APPLIED SCIENCES

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1 ADVANCES in NATURAL and APPLIED SCIENCES ISSN: Published BY AENSI Publication EISSN: Special; 9(17): pages Open Access Journal Performance Enhancement In Single Phase Induction Motor A Novel Approach Using Labview 1 Jethose V. and 2 Manoharn S. 1 Associate Professor & Head, Department of EEE, JCT College of Engineering and Technology. 2 Professor & Head, Department of EIE, Karpagam College of Engineering and Technology. Received 12 February 2015; accepted 20 March 2016; published 25 March 2016 Address For Correspondence: Jethose V., Associate Professor & Head, Department of EEE, JCT College of Engineering and Technology. Copyright 2016 by authors and American-Eurasian Network for Scientific Information (AENSI Publication). This work is licensed under the Creative Commons Attribution International License (CC BY). ABSTRACT Single phase induction motors have numerous and diversified applications, both in homes and the industry. It is safe to say that single phase induction motor applications far outweigh three phase motor applications in the domestic sector. But it operate at low power factors and less efficient than three phase induction motors. So even a small amount of improvement in efficiency will have a bigger effect in conserving energy. This paper incorporates performance analysis of single phase induction motor where auxiliary winding is connected with capacitive load when the SIPM achieves the Rated speed using LabVIEW technology. The auxiliary winding which is used to start the Single phase induction motor got disconnected when the speed of the motor reaches 75% of the rated speed. Then the motor will run by the excitation of the main winding. When the motor starts running with main winding, the part of the generated flux will induce an emf in the auxiliary winding. The emf which induces in the auxiliary winding is not utilized as it is a open circuit ends. By closing the circuit with a Capacitive Load across the auxiliary winding causes a tremendous change in the power quality metries of the machine. As a result the efficiency of the Single phase induction motor is increased. KEYWORDS: Single phase Induction Motor, LabVIEW, Auxiliary Winding, Resistive Load. INTRODUCTION Among electrical motors, induction motors are the most used both for home appliances and in various industries. Most of the electrical energy produced is consumed by these motors. In an effort to improve the efficiency, there have been improvements in materials, design and construction techniques. However motor losses are still greatly dependent on control strategies, especially when the motor operates at light load. Single Phase Induction Motors (SPIMs) is a highly efficient machine when operated close to its rated torque and speed. However, at light loads, no balance in between copper and iron loss, results in considerable decrease in efficiency [9, 10]. To achieve better efficiency induction motor has to be controlled by some control techniques. Variable frequency drives serve the purpose to a good extent but it is not economical to use inverters for a low rating motor as the cost of inverter might exceed the cost of motor. Induction motors are the most extensively used motors for appliances like industrial control, and automation; hence, they are often called the work horse of the motion industry. As far as the robustness, reliability, durability, power factor, ripples, stable output voltage and torque are concerned, Single phase induction motor stands at the a top of the order, to be used for motor control in place of mechanical gears. But the Motor efficiency is considerably Low. To Cite This Article: Jethose V. and Manoharn S., Performance Enhancement In Single Phase Induction Motor A Novel Approach Using Labview, Advances in Natural and Applied Sciences. 9(17); Pages:

2 312 Jethose V. and Manoharn S.., 2015/ Advances in Natural and Applied Sciences. 9(17) Special 2015, Pages: The improvement of Efficiency of Single Phase Induction Motor is the Important Step to be made in Electrical Industry [5, 7]. Various aspects are considered in improving Efficiency. Many aspects mainly concentrated on the Input side of the Induction Motor. Problem Defenition: As we know the fact that a single phase induction motor suffers 2 to 4 times inefficient than a three phase induction motor. This is due to poor power factor and high losses [13]. This paper deals with a novel approach to improve the power factor and efficiency thereby improving the performance of the machine. Single phase capacitor start induction run motor starts with the help of an auxiliary winding connected to the capacitor and its get disconnected when the machine reaches 75% of rated speed. As the rotor rotates, the stationary auxiliary winding gets induced with an emf by generator action [13]. The voltage induced in the auxiliary winding is not utilized. When a capacitive load is connected across the auxiliary winding, it draws active power to improve the power factor and thereby increasing the efficiency. Existing System: Since the single phase induction motor does not have a starting torque, it needs special methods of starting. The stator is provided with two windings, called main and auxiliary windings, whose axes are spaced displaced 90 Electrical degrees. The auxiliary windings are excited by a current which is out of phase with the current in the main winding, both currents derived from the same supply. If the phase difference between the two currents is 90 o and the mmfs created by them are equal, maximum Torque is produced. The auxiliary winding is disconnected by a centrifugal switch after the motor has achieved about 75% of speed. For accurate switching, power Electronics Devices are used in existing system. Proposed System: The auxiliary winding which is used to start the Single phase induction motor got disconnected when the speed of the motor reaches 75% of the rated speed. Then the motor will run by the excitation of the main winding. Here only the supply to the auxiliary winding is disconnected but we cannot disconnect the auxiliary winding. So when the motor run by the main winding, the part of the generated flux will induce the current in the auxiliary winding, since the auxiliary winding got disconnected, the emf which induces in the auxiliary winding will become loss [18]. If the above loss is eliminated, the efficiency of the induction motor will be decreased. The Proposed System implements the optimization in which Resistive Load is placed along with the auxiliary winding. The Resistive Load eliminates the loss due to auxiliary winding and thus the efficiency of the Single phase induction motor is increased. Equivalent Circuit: The steady state model for a single winding of a single phase induction motor is developed in this section. It should be noted that the steady state circuit model does not include effects such as pulsating torques [12]. It also

3 313 Jethose V. and Manoharn S.., 2015/ Advances in Natural and Applied Sciences. 9(17) Special 2015, Pages: doesn't apply to the case where a split-phase winding is used (with or without capacitors). In that case, the backwards rotating field may be completely or partially eliminated. Assuming a single-phase single-winding motor, the equivalent circuit at standstill may be drawn as Note that this circuit is identical to the the per-phase circuit of a multi-phase induction machine at standstill. Now, assuming that the pulsating field in the motor can be described using forwards and backwards rotating fields, the standstill circuit can be modified as shown below. In the diagram shown above, the total impedance is equal to the original circuit, but the magnetising and rotor branches have been divided into two equal components, with forwards and backwards currents to represent the forwards and backwards magnetic fields. Now, if the rotor rotates, the equivalent rotor resistance in each of the forwards and backwards circuits will be divided by slip, relative to the forwards or backwards rotating field. In the final circuit, shown above, forwards slip is shown as s f and backwards slip is shown as s b. These slips are defined as Analyzing the circuit, rather than solve for the currents in the various parallel paths, it is easier to think in terms of impedances of the different parts of the circuit and the power flow into each part of the circuit.

4 314 Jethose V. and Manoharn S.., 2015/ Advances in Natural and Applied Sciences. 9(17) Special 2015, Pages: The phase input impedance is given by Considering the circuit and remembering that air gap power is defined as the input power minus the power losses in the stator, the air gap power can be defined using When considering the torque components, we must remember that the forwards and backwards torques correspond to positive and negative synchronous speeds. Using knowledge from three-phase machines, torque is given be airgap power divided by synchronous speed: Power converted to mechanical energy can be found from the torque and mechanical speed The losses in the rotor circuits can be found from the difference between airgap power and output power Finally, the output power available on the shaft is given by the mechanical power converter minus the rotational losses. P out = P conv - P rot Simulation:

5 315 Jethose V. and Manoharn S.., 2015/ Advances in Natural and Applied Sciences. 9(17) Special 2015, Pages: Single phase induction motor was modeled with the help of LabVIEW software this allows us to model and simulate the motor in order to analyze the performance [1]. The induction motor modeled here was based on the mathematical equations [2, 3, 4]. Front Panel: The Front Panel is used to interact with the user when the program is running. Users can control the program, change inputs, and see data updated in real time. Block Diagram: The block diagram contains this graphical source code. Front panel objects appear as terminals on the block diagram. Additionally, the block diagram contains functions and structures from built-in LabVIEW VI libraries. It is observed that there is great improvement in the power factor and efficiency at all the loads. The improvement saturates when it reaches above 75% of the rated load. The power developed in auxiliary winding adds up with the mechanical output power and increases the total output power. When the machine is loaded 40% of its rated load, the increase in output power is about 18% of he conventional output power at that load. The power factor increased by 5% and efficiency increase by 6%. At 50% the output power increases by 68%, Power factor by 29% and efficiency by 11%. At 65% the output power increases by 14% power factor by 11% and efficiency by 5%. Experimental Setup:

6 316 Jethose V. and Manoharn S.., 2015/ Advances in Natural and Applied Sciences. 9(17) Special 2015, Pages: Conclusion: The performance analysis of Single phase Induction Motor has been done when Capacitor bank is connected across the Auxiliary winding. Simulation results shows the performance of induction motor presented in terms of rotor speed, electromagnetic torque, line voltage, line current, rotor and stator phase current wave form. Also the results of Single phase induction motor which auxiliary winding connected with capacitance bank gives better power factor and efficiency than the conventional System. The result paired with National Instruments LabVIEW is a good simulation tool for modeling and analyzing the performance of Single phase induction motor. Both simulated results and experimental results show very good performance. REFERENCES 1. Nidheesh Nair, K., B. Umamaheswari, LabVIEW Based Performance Optimization of Single Phase Induction Motors. World Congress on Engineering and Computer Science, II, San Francisco, USA. 2. MohdNorishamFadhly Bin Mat Ariffen, Performance study of Induction Motor using Virtual Instrument. 3. Ramprasath, E., P. Manojkumar, Modelling and Analysis of Induction Motor using LabVIEW. International Journal of Power Electronics and Drive System (IJPEDS) 5(3): 344~354 ISSN: Zhaoxian Zhou and James Matthew Johnson, LabVIEW Simulation of Induction Motors ASEE Southeast Section Conference 5. Manoharan, S., N. Devarajan, S.M. Deivasahayam and G. Ranganathan, Review On Efficiency Improvement In Squirrel Cage Induction Motor By Using DCR Technology, Journal of Electrical Engineering, 60(4): Manoharan, S., N. Devarajan, M. Deivasahayam and G. Ranganathan, Energy Conservation in Submersible Pump Sets through Efficiency Improvements using Modified Slot Design and DCR Technology, Journal Electrical Systems, 6-2: Lipo, T.A and D.W. Novotny, Induction machine effciency improvement by voltage control. 8. Sundareswaran, K., An improved energy saving scheme for capacitor-run induction motors, IEEE Transactions on Industrial Electronics. 9. Mademlis, C., I. Kioskeridis and T. Theodoulidis, Optimization of single-phase induction motors Part I:Maximum energy efficiency control, IEEE Transactions on Energy Conversions 10. Vaez-Zadeh, S. and B. Zahedi, Efficiency optimization control of single phase induction motor drives, IEEE Transactions on power electronics. 11. Blaabjerg, F., F. Lungeanu, K. Skaug and A. Aupke, Comparison of variable speed drives for singlephase induction motors, Power Convers. Conf. 12. Yeadon, W.H. and A.W. Yeadon, Handbook of Small Electric Motors New York: McGraw-Hill. 13. Boldea, I. and S.A. Nasar, The Induction Machine Handbook. New York: CRC Press. 14. Wieczorek J.P., O. Gol, and Z. Michalewicz, "An Evolutionary Algorithm For The Optimal Design Of Induction Motors," IEEE Trans.on Magnetics, 34(6): Üler, G.F, O.A. Mohammed and C.S. Koh, "Design Optimization of Electrical Machines Using Genetic Algorithm," IEEE Trans. On Magnetics, 31(3): Trickey, P.H., Design of capacitor motors for balanced operation, Northeastern District Meeting Of The AIEE, pp: Terrance, A., Lettenmaier and Donald W. Novotny, Single Phase induction Motor with an Electronically controlled capacitor, IEEE transactions on Industry Applications, 27(1): Subramanian, R, S.N. Sivanandam, V. Jethose and A.M. Selvaraj, Fuzzy logic based optimization of capacitor value for single phase open well submersible induction motor, International Journal on Soft Computing- IJSC, ISSN: , 01(03): Subramanian, R., S.N. Sivanandam and C. Vimalarani, An Investigation on the Design Optimization Techniques of Electrical Machines using Genetic Algorithm International Journal of Highly Reliable Electronic Systems IJHRES, July December Issue, pp: Wieczorek, J.P., O. Gol and Z. Michalewicz, "An Evolutionary Algorithm For The Optimal Design Of Induction Motors," IEEE Trans.on Magnetics, 34(6):